1. Field of the Invention
The present invention relates to wheelchairs. In particular, the present invention is related to wheelchairs which provide access to the wheelchair from ground level.
2. Description of the Related Art
Wheelchairs are well known in the art and have been in existence for many years. Wheelchair design has undergone extensive modification and refinement, yet the basic design of most wheelchairs has remained relatively consistent. Typical wheelchairs of the past had two large drive wheels connected by an elongated rigid axle supporting a frame or seat on which an individual may be seated. Later versions of the wheelchair eliminated the elongated axle connecting the large drive wheels, but the support frame or other structural members prevented the seat from being moved below a pre-established height.
Some physically disabled persons utilizing a wheelchair, such as paraplegics having normal upper body strength, may engage in physical exercises conducted while sitting or lying supine on the floor or ground. Such a person may also desire to sit on the ground for gardening or for playing with their young children or grandchildren. Such persons commonly require assistance to be lowered to the floor or ground from a conventional wheelchair seat to perform such exercises or tasks.
Exemplary of the related art are the following: U.S. Pat. Nos. 3,123,400; 4,415,202; 5,601,302; and 6,467,785; U.S. Patent Application Publication Numbers U.S. 2003/0218310 A1 and U.S. 2004/0075237 A1; European Patent Publication EP 1 133 968 A3; Japan Publication Number 2001299822 A and Japan Publication Number 2002153514 A.